import java.util.HashSet;
import java.util.Set;

public class StudentCountVisitor implements PaperSelectionVisitor {
    private int count;

    @Override
    public void visit(PaperSelection selection) {
        Set<Student> uniqueStudents = new HashSet<>(selection.getSelections().values());
        this.count = uniqueStudents.size();
    }

    public int getCount() { return count; }
}
